This eccentrically decorated palace is replete with grottoes, fountains, tunnels, and caves.

The most iconic structure in Scotland has been home to bishops, colonels, and Sean Connery characters.

This massive library holds what was once the largest book collection in the world.

This secluded aqua waterfall in the Grand Canyon is the perfect swimming hole, and the Havasupai tribe's fiercely protected natural wonder.

A hidden network of subterranean passageways lies tangled beneath Indianapolis' bustling City Market.

Ruined 11th century abbey built by King David I in Edinburgh, Scotland.

There is no trying to fall in love with this Star Wars fountain, you just do or do not.

These azure waters were thought to lead to the Mayan Underworld.

This dramatic landscape hidden on the Isle of Skye looks as though you've stepped into the magical realm.

Explore the largest pure gypsum deposit in the world, and go dune sledding while you're at it.

An unfortunate geological resemblance to Satan has labeled this Pasadena gorge as a passage to the underworld.

Breathtakingly blue walls shimmer inside the "Glacier Behind the Town."

Tubing through a cave lit with glowworms is a magical underground experience.

An acoustic anomaly with a mysterious cause.

Bioluminescent firefly squid light up this Japanese fishing port.

Oh, just a motel on the edge of the desert decorated with thousands of clowns conveniently located next to an abandoned graveyard.

Centuries-old bridges grown from tangled roots.

Hundreds of lucky felines haunt the ruins where Caesar was murdered.

The very center of Paris is surrounded by a bevy of strange good luck rituals.

Walk 2,300 feet above the ground on the "Troll's Tongue."

New York City's smallest piece of private property.

This strange seaside tower got its name from a wealthy eccentric who would hide coins among its stones.

The only swimming pool listed on the National Register of Historic Places is emptied and refilled each day with naturally filtered water.

High atop the Eiffel Tower is a small apartment built exclusively to entertain the science elite and make the rest of Paris jealous.